I always have a soft spot for 2D RPGM games, but this one is pretty terrible. It has no combat system, despite fighting being a core motivator of the story. Speaking of the story -- look I don't ask for much in porn plots, I can already expect that the characters will be walking around fucking like bonobos at the drop of a hat, but I want a little more than nothing -- the justification for why the game gives you a strict time limit is nonexistent. After the fourth level, if Erin's Libido is too high, control is completely taken away from you, and you are railroaded into the bad ending. Which, given the village's men want to treat her like a brood mare, just raises the question of why they didn't do that from the start. Even the "good" endings aren't much better. She's either a breeding slave, a fuckbuddy, or a breeding slave but maybe her husband will rescue her?
In terms of technical problems, it's clear the developer has no idea how to program the Gallery, because there is no way to leave once you have entered. You have to pause and click gallery again, which is a problem, because the end drops you in the gallery without that exit option. Meaning you hopefully have a save to load. Heaven help you if you didn't save before beating the fourth floor on high Libido.
Overall a good lesson on what not to do in RPGM. It has some potential (the art is okay but very pixelated), but none that hasn't already been capitalized on by other games. If you're looking for much better games in this style, check out Ariadne or Ideology in Friction. Alternatively, if you are looking for something which is less of a time sink, I would recommend most of Heisendou's catalogue.